Health psychology (option): animals in research, data and evaluation

Why use animals in stress research?

Practical reasons: researchers can control the environment and history completely; procedures that would be unethical with humans (long-term stress, measuring organ damage) can sometimes be done; short life cycles allow study of long-term effects; physiological stress systems (HPA axis) are similar in mammals.

Practical problems: animals differ from humans in brains, cognition and social life, so generalising is risky (Selye's rats, Brady's monkeys); animals cannot appraise stress in human ways (work, exams, money); laboratory stress may itself affect results.

The Animals (Scientific Procedures) Act 1986

In the UK, research on protected animals is regulated by the Animals (Scientific Procedures) Act 1986 (ASPA), enforced by the Home Office:

• Three licences: an establishment licence (the place), a project licence (the programme of work, after a harm-benefit assessment) and a personal licence (each researcher, showing they are competent).
• Work must apply the 3Rs: Replace animals with alternatives where possible; Reduce the number used; Refine procedures to minimise suffering.
• Benefits must outweigh harms, and humane end points must be set.

Brady's (1958) study, with severe suffering and deaths, would be very unlikely to pass a harm-benefit assessment today.

Ethical arguments and evaluation

• For: the potential benefits for human health (understanding stress and illness) may justify carefully regulated research; animals are protected by law.
• Against: animals cannot consent; suffering may be severe; if animals are similar enough to humans for findings to generalise, they may be similar enough to suffer in similar ways (a dilemma); alternatives (human studies of cortisol, brain scans) increasingly exist.

Evaluating health research (7.3.4): Evaluate in the terms the specification uses: reliability, validity, generalisability, credibility, objectivity and subjectivity, ethics and practical application. For example, Brady's yoked control gives control but poor generalisability; Avdagic et al.'s randomisation supports cause and effect; Nakonz and Shik's ethnography is high in validity but low in generalisability.

Data (7.3.3): use List A (means, medians, SD, percentages, graphs) and List B (chi-squared, Spearman, Wilcoxon, significance levels, Type I and II errors) where appropriate, as practised in the life events and CBT lessons.

Worked example

Apply the 3Rs to a proposed study of stress and ulcers in rats.

1. **Replace**: could the question be answered with human participants (cortisol and self-report) or cell studies instead?
2. **Reduce**: use a power calculation to use the fewest rats needed.
3. **Refine**: use the mildest stressor that answers the question, monitor health and stop at humane end points.

Answer: Replace if possible, reduce numbers, refine procedures.

Check yourself

1. What are the 3Rs in animal research?
   • Respect, responsibility, reliability
   • Review, report, repeat
   • Restrain, reward, release
   • Replace, reduce, refine
   Show answer

   Replace, reduce, refine. Replace, reduce, refine.

2. Under ASPA 1986, which licence covers an individual researcher?
   • A project licence
   • A personal licence
   • An establishment licence
   • A driving licence
   Show answer

   A personal licence. Each person needs a personal licence.

3. In what year was the Animals (Scientific Procedures) Act passed?
   Show answer

   1986. 1986.

4. Using the mildest possible stressor and monitoring animals' health is an example of
   • refinement
   • replacement
   • reduction
   • randomisation
   Show answer

   refinement. Refinement minimises suffering.

5. Which is a practical reason for using animals in stress research?
   • They can appraise exam stress like humans
   • They can give informed consent
   • Their environment and history can be fully controlled
   • Their brains are identical to humans'
   Show answer

   Their environment and history can be fully controlled. Control.

6. Explain one problem with generalising from animal stress research to humans.
   Show answer

   Animals differ from humans in brain structure and cognition, so they do not appraise stressors in the same way; human stress often involves thoughts about work, money or relationships, which animal studies cannot capture.. Difference plus why it matters.

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Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Psychology specification, Issue 6 (November 2024, first assessment January 2026)
• GOV.UK: Research and testing using animals, licences and compliance
• Pearson IAL Psychology summary of studies: WPS03
• Brady, Porter, Conrad and Mason (1958), Avoidance behavior and the development of gastroduodenal ulcers, Journal of the Experimental Analysis of Behavior 1

Last updated 8 November 2026. Spotted a mistake? Tell us.